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A high pressure supercritical CO 2 (HP-ScCO 2 ) geochemical reactor was used to simulate CO 2 sequestration into deep coal seam under around 40 °C and 9.8 MPa for 72 h and fractal analysis were employed to study the mercury intrusion data of 4 different coal rank samples before and after the ScCO 2 –H 2 O treatment, focusing on the pore structure. It is revealed from the mercury porosimetry data that after exposure to the ScCO 2 –H 2 O fluid, the true density of coal samples are changed as well as total pore volume and porosity most importantly in the increase of micro-pore range. Fractal analysis is introduced to distinguish inter- and intraparticle pores at lower mercury intrusion pressure and to identify the initial pressure associated with the coal compressibility. Three values of fractal dimension ( D 1 , D 2 and D 3 ) are obtained under different pressure ranges, which can be classified corresponding to three different mercury intrusion processes. Varied D 1 values are mainly due to the accumulation mode of samples in the penetrometer and can be used to distinguish the interpore and intrapore intrusion process at lower pressure range of mercury intrusion. D 2 values represents the mercury intrusion into intrapores. D 3 value is decreasing as coal rank increased and can be used to describe the initial pressure when coal samples begin to be compressed or deformed at higher pressure of mercury intrusion. The experiments revealed that CO 2 sequestration process changed the physical properties of coal samples, especially in compression resistance. Coal rank and ash content in coal are very important factors which will affect the variation of coal structure during CO 2 sequestration. [ABSTRACT FROM AUTHOR]

Abstract: In order to study the extensively genetic diversities of more than 700 cultivars of Chinese jujube, it is necessary to utilize various informative DNA markers. SSR markers are highly polymorphic, co-dominant, locus-specific markers widely used in genetic studies, but less used in Chinese jujube because of no specific primers available. In this study, we used the approach of selectively amplified microsatellite (SAM) to develop SSR markers for Chinese jujube and its related species. Three cultivars (Dongzao, Dalilongzao and Jinsixiaozao) were selected to perform the approach of SAM with CT repeats. There were totally 25 primers obtained, of which we selected 16 primers available to detect the polymorphism in populations of 24 Chinese jujube cultivars, two wild jujube varieties and two Indian jujube cultivars. Based on these primers, genetic relationships of the 28 samples were constructed in a dendrogram according to the UPGMA cluster analysis. The samples were clustered into three main groups, including Chinese jujube, wild jujube and Indian jujube as expected. The 16 sequence-specific SSR primers could efficiently distinguish all the 24 cultivars of Chinese jujube, except for two cultivars, Jinsixiaozao and its ‘stoneless’ mutant, Wuhexiaozao. As a result, SAM was a very efficient method in targeted developing sequence-specific SSR primers in Chinese jujube. Furthermore, SAMs could also be used as high polymorphic molecular markers independently. The further study would focus on developing other oligonucleotide repeat types and applying more SSRs available in the genetic research of Chinese jujube. [Copyright &y& Elsevier]

Abstract: Pore structure changing of coal during the CO2 geo-sequestration is one of the key issues that affect the sequestration process significantly. To address this problem, the CO2 sequestration process in an anthracite coal was replicated using a supercritical CO2 (ScCO2) reactor. Different coal grain sizes were exposed to ScCO2 and water at around 40°C and 9.8MPa for 72h. Helium pycnometer and mercury porosimetry provide the density, pore size distribution and porosity of the coal before and after the ScCO2 treatment. The results show that after exposure to the ScCO2–H2O reaction, part of the carbonate minerals were dissolved and flushed away by water which made the true density increased as well as total pore volume and porosity most importantly in the micro-pore range. Hysteresis between mercury intrusion and extrusion was observed. Ink bottle shaped pores can be either damaged or created compared with the ScCO2 treated coal samples. This suggests that the ScCO2 treatment most likely increase the volumes of pores in anthracite coal, which also contributed to the increase in porosity of the treated samples. Therefore the CO2 sequestration into coal appears to have the potential to increase significantly the anthracite microporosity which is very advantageous for CO2 storage. [Copyright &y& Elsevier]

Abstract: Metal hydride heat pump (MHHP) can be utilized in a variety of applications and shows great potential in recovery of low-grade heat. Being its kernel component, the reactors should facilitate good heat and mass transfer to achieve satisfactory system performance. In this paper, the influences of certain heat transfer enhancement measures for the reactors were investigated by numerical simulation and thermodynamic analysis. Three types of reactors packed with metal hydride powder, metal hydride powder/Al foam and metal hydride compact were taken for discussion. As shown in the simulation results, for the MHHP adopting heat transfer enhancement, the coefficient of performance tends to reduce slightly while the specific heating power increases remarkably. Therefore, these measures work positively and are recommended for use in heat pump applications. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents experimental investigations on CO2/CH4 binary gas flow in bulk coal under controllable stress conditions, focusing on sorption-induced swelling/shrinkage and gas permeability associated with CO2-sequestration enhanced coalbed methane (CO2-ECBM) recovery. The gas flush tests with carbon dioxide were conducted on a specially designed true tri-axial stress coal permeameter (TTSCP) using a large coal sample pre-adsorbed methane. These tests simulate the in-situ conditions of CO2-ECBM recovery from coal and provided experimental information for better understanding of the gas transport in coals. The swelling/shrinkage coefficients of coal associated with CO2-ECBM process have been evaluated using the experimental data. The results show that adsorption and desorption of gases CH4 and CO2 can significantly affect the volumetric change of micro- and macropores in coal, leading to coal swelling/shrinkage and fluctuation of permeability, and hence controlling the transport and flow of gases through coal. [Copyright &y& Elsevier]

Abstract: The metal hydride reactors are widely used in many industrial applications, for example, hydrogen storage, heat pump, thermal compression, gas separation, etc. The performance of the reactor is greatly affected by its design, which deserves careful study. Given the complicated nature of the hydride formation/decomposition processes, a series of technical issues are involved in the design of metal hydride reactors, such as primary configuration, thermal management, hydrogen transfer and mechanistic strength. These issues should be well addressed to fulfil the requirement of specific application. In this paper, the representative achievements with regards to the design issues so far were reviewed in detail, and some comments were made accordingly. It was concluded that an optimized reactor design comes from integrated considerations of numerous factors, particularly requirements for the applications and characteristics of the metal hydride system. The analytic hierarchy process was recommended for use in the selection of the optimum reactor scheme. [Copyright &y& Elsevier]

Abstract: In this study, plasma nanocoatings with thickness of less than 50nm were deposited onto two types of intravascular stents made of nitinol (NiTi alloy) and stainless steel from gas mixtures of trimethylsilane (TMS) and oxygen (O2) in a direct current (DC) plasma reactor system. The surface properties, surface morphology, and surface chemistry of the plasma coated stents were characterized using surface contact angle measurements, scanning electron microscopy (SEM), and energy dispersive spectrometer (EDS). In order to investigate their surface endothelialization effects, plasma coated stents were seeded with human umbilical vein endothelial cells (HUVECs) for cell culture study. The cell culture data showed that plasma nanocoatings deposited from a gas mixture of TMS:O2 =1:3 gave rise to a statistically significant increase in adhered cell numbers, which were 79.75±6.18 on nitinol stents vs. 41.25±9.38 cells on uncoated bare controls and 119.50±12.40 on stainless stents vs. 56.85±12.53 cells on uncoated bare controls. These results evidently demonstrated that plasma nanocoatings prepared from appropriate plasma chemistry or gas composition could significantly enhance the surface endothelialization on both nitinol stents and stainless steel intravascular stents. [Copyright &y& Elsevier]

Abstract: The restoration of macrophytes in eutrophic shallow lakes has been the focus of active research in the past decade. The approach of building up a mosaic community of macrophytes (MCMs) to improve water quality and remediate the ecosystems of lakes is proposed in this paper. Several species of floating, floating-leaved, and submerged macrophytes were introduced in experimental enclosures in eutrophic shallow lakes. These macrophytes were intercropped in small patches and formed mosaic communities of spatial and temporal combinations (spatial and seasonal mosaic patterns) in the lakes. Macrophytes can improve water transparency quickly and the MCM system can stabilize this clear water state over a long time in turbid eutrophic shallow lakes. The constructed MCM created heterogeneous habitats that are favourable for different macrophytes and for the growth and succession of other organisms, as well as for removing water pollutants. When the eutrophic water flowed through the MCM system at a retention time of 7 days, the removal efficiency rates of the MCM system for algae biomass, NH4 +–N, TN, TP and PO4 3−–P were 58%, 66%, 60%, 72% and 80%, respectively. [Copyright &y& Elsevier]

Abstract: An alternative approach is proposed to develop an improved permeability model for coalbed methane (CBM) and CO2-enhanced CBM (ECBM) recovery, and CO2 geosequestration in coal. This approach integrates the textural and mechanical properties to describe the anisotropy of gas permeability in coal reservoirs. The model accounts for the stress dependent deformation using a stress–strain correlation, which allows determination of directional permeability for coals. The stress–strain correlation was developed by combining mechanical strain with sorption-induced strain for any given direction. The mechanical strain of coal is described by the general thermo-poro-elastic constitutive equations for solid materials under isothermal conditions and the sorption-induced strain is approximated by treating the swelling/shrinkage of coal matrix equivalent to the thermal contraction/expansion of materials. With directional strains, the permeability of coal in any given direction can be modeled based on the theory of rock hydraulics. In this study, the proposed model was tested with both literature data and experiments. The experiments were carried out using a specially designed true tri-axial stress coal permeameter (TTSCP). The results show that the proposed model provides better predictions for the literature data compared with other conventional coal permeability models. The model also gives reasonable agreement between the predicted and measured stress–strains and directional permeabilities under laboratory conditions. [Copyright &y& Elsevier]

Abstract: The variations of critical axial forces for the inner and outer tubes of the double-walled carbon nanotube (DWCNT) in different buckling modes are studied in this paper. The effects of growth in the radius, length, and aspect ratio (length/radius) on the stability of a DWCNT and its inner and outer tubes are also considered, while the effects of the surrounding elastic medium on the outer tube and the van der Waals forces between two adjacent tubes are taken into account. Comparison between the DWCNT as a whole, its outer tube, inner tube, and single-walled carbon nanotube (SWCNT) indicates that the critical axial force of the inner tube of a DWCNT is almost two times more than the critical axial force of a SWCNT, showing the positive effect of the van der Waals interaction on the inner tube, DWCNT surrounded by an elastic medium has greater axial stability than DWCNT, without the surrounding elastic medium. This study demonstrates that the critical axial force of DWCNT is larger than for SWCNT, and it rises as the radius and aspect ratio increase. [Copyright &y& Elsevier]

Abstract: Semiconductor tin oxide (SnO2) nanotubes have been synthesised in bulk quantities using a sol–gel template (AAO membrane) synthetic technique. The morphology and crystal structure of SnO2 nanotubes were characterised by a field emission scanning electron microscope (FESEM) and a transmission electron microscope (TEM). The as-prepared SnO2 nanotubes are polycrystalline with an outer diameter of 200nm, an inner diameter of about 150nm and a length extending to tens of micrometers. SnO2 nanotube sensors exhibited high sensitivity towards ethanol gas. [Copyright &y& Elsevier]

Abstract: LiFePO4/carbon and LiFe1−x Co x PO4/carbon (x =0.02, 0.04, 0.08 and 0.1) composite cathode materials were synthesized by citrate gel technique. X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to study the phase and morphology of un-doped and Co doped lithium iron phosphate/carbon composites. The SEM images revealed that the particles were agglomerated and the particle sizes were almost homogeneously distributed. The particle size was found to be between 200 and 300nm from transmission electron microscopy. Cyclic voltammetric studies were taken to investigate the electrochemical performance of the prepared composite materials. The high intensity of the anodic and cathodic peaks indicates that Li-ions and electrons were participating actively in redox reactions due to the carbon coating. Charge/discharge studies carried out on a CR2032 coin cell revealed that the carbon coated LiFePO4/carbon composite exhibited an improved discharge capacity of 157mAh/g at low rates. We found that cobalt doping does not have a favourable effect on the electrochemical performance of lithium iron phosphate cathode materials. [Copyright &y& Elsevier]

Abstract: The role of inorganic ceramic fillers namely nanosized Al2O3 (15–25nm) and TiO2 (10–14nm) and ferroelectric filler SrBi4Ti4O15 (SBT CIT) (0.5μm) synthesized by citrate gel technique (CIT) on the ionic conductivity and electrochemical properties of polymer blend 15wt% PMMA+PEO8:LiClO4+2wt% EC/PC electrolytes were investigated. Enhancement in conductivity was obtained with a maximum of 0.72×10−5 Scm−1 at 21°C for 2wt% of SrBi4Ti4O15 (SBT CIT) composite polymer electrolyte. The lithium-ion transport number and the electrochemical stability of the composite polymer electrolytes at ambient temperature were analyzed. An enhancement in electrochemical stability was observed for polymer composites containing 2wt% of SrBi4Ti4O15 (SBT CIT) as fillers. [Copyright &y& Elsevier]

Abstract: ZrO2 nanolayer coated LiFePO4 particles were successfully prepared by a chemical precipitation method. Nanolayer structured ZrO2 was found on the surface of LiFePO4 particles by high resolution transmission electron microscopy (HRTEM). The coating does not affect the crystal structure of the LiFePO4 core, as determined by X-ray diffraction (XRD) and selected area electron diffraction (SAED) on individual particles. The ZrO2 coating can remarkably improve the electrochemical performance at high charge/discharge rate. This improvement may be due to the amelioration of the electrochemical dynamics on the LiFePO4 electrode/electrolyte interface resulting from the effects of the ZrO2 nanolayer coating. [Copyright &y& Elsevier]

Abstract: Layered intercalation compounds LiM0.02Co0.98O2 (M=Mo6+, V5+, Zr4+) have been prepared using a simple solid-state method. Morphological and structural characterization of the synthesized powders is reported along with their electrochemical performance when used as the active material in a lithium half-cell. Synchrotron X-ray diffraction patterns suggest a single phase HT-LiCoO2 that is isostructural to α-NaFeO2 cannot be formed by aliovalent doping with Mo, V, and Zr. Scanning electron images show that particles are well-crystallized with a size distribution in the range of 1–5μm. Charge–discharge cycling of the cells indicated first cycle irreversible capacity loss in order of increasing magnitude was Zr (15mAhg−1), Mo (22mAhg−1), and V (45mAhg−1). Prolonged cycling the Mo-doped cell produced the best performance of all dopants with a stable reversible capacity of 120mAhg−1 after 30 cycles, but was inferior to that of pure LiCoO2. [Copyright &y& Elsevier]

This paper presents an alternative model of multicomponent gas diffusion and flow in bulk coals, focusing on counter-diffusion associated with -sequestration enhanced coalbed methane (-ECBM) recovery. The model was developed based on the bidisperse diffusion mechanism and the Maxwell–Stefan (MS) diffusion theory, which provides an improved simulation of multicomponent gas diffusion dynamics. The model was firstly validated under the condition of pure gas diffusion by comparing with the analytical solutions of a bidisperse diffusion model and the experimental data obtained from pure-gas sorption kinetic tests. Then it was numerically solved by considering counter-diffusion and flow in a large coal sample to simulate a laboratory -injection core flush experiment. The simulation shows an excellent agreement with the flush experiment. A quantitative description of the relationship between micropore diffusivity and concentration has been achieved, which is a deficiency in currently available CBM/ECBM models. The concentration-dependent diffusivities need to be taken into account in modeling the coalbed methane (CBM) recovery, in particular for simulation of ECBM production from and sequestration in coal seams. [Copyright &y& Elsevier]

Abstract: This paper presents the development of an analytical model which can be used to relate the structural parameters of coal to its mechanical properties such as elastic modulus and Poisson’s ratio under a confined stress condition. This model is developed primarily to support process modeling of coalbed methane (CBM) or CO2-enhanced CBM (ECBM) recovery from coal seam. It applied an innovative approach by which stresses acting on and strains occurring in coal are successively combined in rectangular coordinates, leading to the aggregated mechanical constants. These mechanical properties represent important information for improving CBM/ECBM simulations and incorporating within these considerations of directional permeability. The model, consisting of constitutive equations which implement a mechanically consistent stress–strains correlation, can be used as a generalized tool to study the mechanical and fluid behaviors of coal composites. An example using the model to predict the stress–strain correlation of coal under triaxial confined stress by accounting for the elastic and brittle (non-elastic) deformations is discussed. The result shows a good agreement between the prediction and the experimental measurement. [Copyright &y& Elsevier]

Abstract: A SnO2–mesoporous organo-silica nanoarray (MOSN) composite was prepared by surfactant mediated synthesis combined with a sol–gel vacuum suction method in which SnO2 has been successfully incorporated inside the periodic nanoholes in the MOSN or coated on its surface. The MOSN with a high aspect ratio of length to width could not only maintain its structure but also effectively accommodate the volume expansion of the SnO2 during electrochemical reactions with Li+. The SnO2–MOSN composite showed a higher reversible capacity of 420mAhg−1 with greatly improved capacity retention and lower initial irreversible capacity compared to SnO2 powder. This interesting anodic performance of SnO2–MOSN composite supports the potential use of MOSN for lithium ion batteries. [Copyright &y& Elsevier]

Abstract: LiFePO4, doped LiM x Fe1−x PO4, and Li1−x M x FePO4 compounds have been prepared via a sol–gel synthesis method. The physical properties of the as-prepared lithium iron phosphates were characterised by X-ray diffraction, X-ray absorption near-edge spectroscopy (XANES), and magnetic susceptibility. The electrochemical properties lithium iron phosphates were tested by a variety of electrochemical techniques. Lithium iron phosphate electrodes demonstrated a stable discharge capacity of 160–165mAhg−1, almost approaching the theoretical capacity. The good electronic conductivity and nanocrystalline could contribute to the unique performance of lithium iron phosphate electrodes. Lithium iron phosphates have a significant potential to be used as a new cathode materials in Li-ion batteries. [Copyright &y& Elsevier]

Abstract: Nickel oxide (NiO) nanotubes have been produced for the first time via a template processing method. The synthesis involved a two step chemical reaction in which nickel hydroxide (Ni(OH)2) nanotubes were firstly formed within the walls of an anodic aluminium oxide (AAO) template. The template was then dissolved away using concentrated NaOH, and the freed nanotubes were converted to NiO by heat treatment in air at 350°C. Individual nanotubes measured 60μm in length with a 200nm outer diameter and a wall thickness of 20–30nm. The NiO nanotube powder was used in Li-ion cells for assessment of the lithium storage ability. Preliminary testing indicates that the cells demonstrate controlled and sustainable lithium diffusion after the formation of an SEI. Reversible capacities in the 300mAhg−1 range were typical. [Copyright &y& Elsevier]

Abstract: Si thin films were deposited directly on stainless steel substrates that act as current collectors using the pulsed laser deposition (PLD) technique. Amorphous Si films of different thicknesses were obtained at the Ar gas pressure of 5×10−5 Torr and a temperature of 500°C but different deposition times. The microstructure and morphology of the films were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and atomic force microscopy (AFM). The anodic electrochemical performance of the films was examined in the range of 0.005–1.5V, which revealed excellent cyclic stability without any large capacity fade up to the 70th cycle. The PLD process was suitable for improving the density and adhesion behavior of the films. [Copyright &y& Elsevier]

Abstract: Coal fired power generation will continue to provide energy to the world for the foreseeable future. However, this energy use is a significant contributor to increased atmospheric CO2 concentration and, hence, global warming. Capture and disposal of CO2 has received increased R&D attention in the last decade as the technology promises to be the most cost effective for large scale reductions in CO2 emissions. This paper addresses CO2 transport via pipeline from capture site to disposal site, in terms of system optimization, energy efficiency and overall economics. Technically, CO2 can be transported through pipelines in the form of a gas, a supercritical fluid or in the subcooled liquid state. Operationally, most CO2 pipelines used for enhanced oil recovery transport CO2 as a supercritical fluid. In this paper, supercritical fluid and subcooled liquid transport are examined and compared, including their impacts on energy efficiency and cost. Using a commercially available process simulator, ASPEN PLUS 10.1, the results show that subcooled liquid transport maximizes the energy efficiency and minimizes the cost of CO2 transport over long distances under both isothermal and adiabatic conditions. Pipeline transport of subcooled liquid CO2 can be ideally used in areas of cold climate or by burying and insulating the pipeline. In very warm climates, periodic refrigeration to cool the CO2 below its critical point of 31.1°C, may prove economical. Simulations have been used to determine the maximum safe pipeline distances to subsequent booster stations as a function of inlet pressure, environmental temperature and ground level heat flux conditions. [Copyright &y& Elsevier]

Abstract: Nanosized pure SnSb and SnSb with excess ductile Sn (referred to as Sn/SnSb) powders have been synthesised by careful reductive co-precipitation in NaBH4. Crystallite sizes for both powders measure in the 50–100nm range with particles agglomerating up to a few micrometers in pure SnSb powder and several tens of micrometers in the Sn/SnSb composite. Pristine powders were mixed separately with carbon black in order to improve dispersion and electronic conduction. Electrodes were constructed using the powders and tested as Li-ion half cell in order to measure the electrochemical performance. The energy storage capacity of electrodes improved in excess of 50% by increasing quantity of carbon black from 20wt.% to 50wt.%. Capacity fade over repeated charge and discharge cycles still remains a challenge to practical application of SnSb and Sn/SnSb alloy electrodes. [Copyright &y& Elsevier]

Abstract: A series of polypyrrole-LiFePO4 (PPy-LiFePO4) composites were synthesised by polymerising pyrrole monomers on the surface of LiFePO4 particles. AC impedance measurements show that the coating of polypyrrole significantly decreases the charge-transfer resistance of LiFePO4 electrodes. The electrochemical reactivity of polypyrrole and PPy-LiFePO4 composites for lithium insertion and extraction was examined by charge/discharge testing. The PPy-LiFePO4 composite electrodes demonstrated an increased reversible capacity and better cyclability, compared to the bare LiFePO4 electrode. [Copyright &y& Elsevier]

Abstract: Carbon coated lithium iron phosphates were prepared by a carbon aerogel synthesis process, through which LiFePO4 particles were embedded in amorphous carbon. The carbon coating effect can significantly enhance the electronic conductivity of LiFePO4. The electrochemical properties of the as-prepared LiFePO4 cathode materials were systematically characterised. The carbon coated LiFePO4 cathode demonstrated a high capacity and stable cyclability. [Copyright &y& Elsevier]

Abstract: Nanosize silver and tin dioxide powders were synthesised by a novel reverse micelle technique. The reverse micelles were formed from a microemulsion of organic solvents, water based salts and surfactants. The spherical nanosize Ag powders were formed via in situ reduction. The tin hydroxide precipitates were formed in reverse micelles and converted to tin dioxide nanopowders after heat treatment. The Ag and SnO2 powders have a particle size in the range of 20–50nm. The as-prepared nanosize Ag and SnO2 nanopowders were used in lithium-ion cells for lithium storage. [Copyright &y& Elsevier]

Abstract: Spherical LiNi0.75Co0.25O2 compounds were synthesized by sintering spherical Ni0.75Co0.25(OH)2 and LiOH·H2O precursors at various temperatures in an oxygen atmosphere. A pure phase LiNi0.75Co0.25O2 could be identified. SEM observation showed that the LiNi0.75Co0.25O2 particles are spherical in shape and are composed of many small crystals. Magnetic susceptibility measurements reveal that the spherical LiNi0.75Co0.25O2 compounds have a more ordered layered structure than that of non-spherical LiNi0.75Co0.25O2. The spherical LiNi0.75Co0.25O2 cathodes demonstrated a stable electrochemical performance in lithium-ion cells with a high reversible capacity of 167mAh/g and good cyclability. [Copyright &y& Elsevier]

Abstract: Several Sn-coated MCMB (mesocarbon microbeads) graphite anode materials were prepared by microencapsulating nanosize Sn particles in MCMB. The nanosized tin particles are homogeneously dispersed in MCMB graphite matrix via electroless in situ chemical reduction. X-ray diffraction and EDS measurement confirms the presence of Sn in MCMB matrix. A systematic electrochemical testing has been performed on the Sn-coated MCMB graphite electrodes. The tin-coated MCMB graphite electrodes demonstrated an improvement in lithium storage capacity. The reaction process of lithium intercalation and de-intercalation in MCMB structure and lithium alloying with tin has been identified by cyclic voltammetry measurement. The micro-encapsulation of Sn in MCMB graphite can enhance the electrochemical properties of MCMB graphite anodes. [Copyright &y& Elsevier]

Abstract: Stoichiometric and non-stoichiometric Mg-doped lithium iron phosphates were synthesised via spray-pyrolysis, followed by sintering at high temperature for crystallization. The spray pyrolysis process allows the homogeneous mixing of the ingredient reactants at atomic level. The electronic conductivities of the Mg-doped lithium iron phosphates have been drastically improved by 4 orders of magnitude, comparing to the undoped LiFePO4. The electrochemical properties of as-prepared lithium iron phosphates were systematically measured by cyclic voltammetry and constant current charge/discharge cycling tests. [Copyright &y& Elsevier]

Nanostructured Si–C composite materials were prepared by dispersing nanocrystalline Si in carbon aerogel and subsequent carbonization. Through this process, nanosize Si was homogeneously distributed in a carbon matrix. The Si–C composites exhibit a reversible lithium storage capacity of 1450 mA h/g when used as anodes in lithium-ion cells. The nanostructured Si–C composite electrodes demonstrated good cyclability. The Si–C composites could provide a novel anode material for lithium-ion batteries. [Copyright &y& Elsevier]

Layered Li[Li0.3Cr0.1Mn0.6]O2 cathode material with a hexagonal structure was synthesized by a solid-state reaction. The structural changes of this material were studied using a synchrotron-based in situ X-ray diffraction (XRD) technique during charge/discharge cycles. The results of in situ X-ray diffraction indicated that the layer structure and the hexagonal symmetry of this material were preserved through the phase transition between H1 and H2 during the charge/discharge cycling. When cycled in the voltage range of 2.0–4.5 V, the changes in lattice parameters a and c are smaller than those for the LiNiO2 layered material. When charged to a high voltage at 5.1 V, the hexagonal phase H3, which is commonly formed at voltages higher than 4.3 V in LiNiO2 with a very short c-axis, is not observed in the Li[Li0.3Cr0.1Mn0.6]O2 cathode, indicating a possible high thermal stability in the fully charged state. Cyclic voltammograms show a single pair of oxidation and reduction peaks, consistent with a reversible phase transition between H1 and H2 observed from the in situ X-ray diffraction data. [Copyright &y& Elsevier]

A series of Sn-coated graphite composite materials for lithium-ion batteries were prepared by microencapsulating nanosize Sn particles in graphite. The nanosize Sn particles are homogeneously dispersed in the graphite matrix via electroless chemical reduction. The tin-graphite composite showed a great improvement in lithium storage capacity. Since Sn is an active element to lithium, Sn can react with lithium to form Li4.4Sn alloys, a reaction accompanied by a dramatic volume increase, whereas the ductile graphite matrix provides a perfect buffer layer to absorb this volume expansion. Therefore, the integrity of the composite electrode is preserved during lithium insertion and extraction. Cyclic voltammetry was employed to identify the reaction process involved in lithium insertion and extraction in the graphite structure, as well as lithium alloying with tin. The tin-graphite composites provide a new type of anode material for lithium-ion batteries with an increased capacity. [ABSTRACT FROM AUTHOR]

LiTi2(PO4)3 with a Na+ superionic conductor (NASICON)-type structure is prepared by a two-step solid-state reaction. X-ray diffraction (XRD) confirms that the LiTi2(PO4)3 compound has a NASICON structure, i.e. rhombohedral (space group: R3c). It is found that lithium can be electrochemically inserted into the LiTi2(PO4)3 structure, with a maximum intake of 5.2 mol of lithium per mole of LiTi2(PO4)3 compound, and that [PO4] tetrahedra can participate in the redox reaction. This corresponds to a lithium-storage capacity of 360 mAh g−1. The kinetic parameters of lithium insertion in LiTi2(PO4)3 NASICON are determined by means of ac impedance technique. The charge-transfer resistance (RCT) and exchange current density (i0) are invariable regardless of the state of lithium insertion. This is associated with the unique structure characteristics of the NASICON skeleton. By contrast, the diffusion coefficient, DLi of lithium varies with the state of lithium insertion. The value of DLi is in the range 1.4×10−11 to 1.2×10−9 m2 s−1, which is much higher than for other intercalation materials. [Copyright &y& Elsevier]

This paper presents the microstructure and hardness of composite solders obtained by the addition of nanopowders of titanium dioxide to a conventional solder. Titanium dioxide powders-reinforced lead (Pb)–tin (Sn) composite solders were prepared by thoroughly blending nano-sized titanium dioxide powders with powders of a eutectic solder and using a water-soluble flux. The blended solder paste was melted and allowed to re-solidify in a crucible placed on a hot plate and maintained at a constant temperature. Optical microscopy observations revealed that for additions of titanium dioxide up to 1 wt.%, the grain size and width of the grain boundary decreased. For the addition of 2 wt.% of titanium dioxide, nanopowders microporosity was observed both at and along the grain boundary regions coupled with the presence of second-phase particles. Microhardness measurements revealed that the addition of titanium dioxide nanopowders is helpful in enhancing the overall strength of the eutectic solder. [Copyright &y& Elsevier]

Nanoparticle-dispersed polymer electrolytes have been prepared by stirring or high-energy ball milling of polyethylene oxide (PEO), lithium salt (LiCF3SO3, LiClO4 and LiPF6), and nanometer-size ceramic powder (TiO2, SiO2 and Al2O3). The smaller the size of ceramic particles, the better they influence the crystallization kinetics of the PEO polymer chains. High-energy ball milling lowers the glass transition temperature of the composite polymers, and thus increases the ionic conductivity greater than the order of the magnitude compared with the un-milled samples. The highest ionic conductivity was reported when using LiPF6 as added lithium salt and Al2O3 as dispersed particle. Cyclic voltametric measurements showed that the PEO-system is electrochemically stable in the range of 2–5 V. [Copyright &y& Elsevier]

LiCoO2 cathode materials have been prepared by a spray-drying technique. The stoichiometry of the materials, their morphology, and the phase composition and electrochemical performance have been studied. The effects of thermal annealing and decomposition processes on the structure are discussed in detail. The changes of Li content in materials were monitored by ICP spectrometry. It was established that the decomposition of the acetates at around 450 °C is a slurry-making process that compacts the powder. It was found that well lithiated samples with good life cycle and high capacity can be prepared using acetate precursors and a spray solution technique. The morphology, grain size and texturing can be controlled by the sintering time and temperature in combination with intermediate grinding. [Copyright &y& Elsevier]

Several multiple-ion-doped lithium nickel oxides with formula of LiMnxCoyNi1−x−yO2 were synthesized via solid-state reactions at high temperature. These phase-pure LiMnxCoyNi1−x−yO2 compounds have a layered hexagonal structure, and their electrochemical properties were systematically investigated. Typical cathodes can deliver a capacity in the range of 140–180 mAh/g with fairly stable cyclability. The kinetics of lithium insertion in these cathodes were characterized via ac impedance measurements. These newly developed compounds show great promises as cathode materials for future lithium-ion batteries with low cost and less toxicity. [Copyright &y& Elsevier]

The synthesis and electrochemical characteristics of LiCoxMnyNi1−x−yO2 as cathode materials for rechargeable lithium-ion batteries were investigated. The precursor CoxMnyNi1−x−y(OH)2 was obtained by the chemical co-precipitation method. LiCoxMnyNi1−x−yO2 (0≤x≤0.3, and y=0.2) was prepared by heating a mixture of CoxMnyNi1−x−y(OH)2 and Li2CO3 at 850–900 °C for 24 h in air. The X-ray diffraction (XRD) patterns indicated that pure phase LiCoxMnyNi1−x−yO2 was obtained. The scanning electron micrographs (SEMs) show that the synthesized LiCoxMnyNi1−x−yO2 compounds have good micro-morphology and uniform particle size. The electrochemical properties of these materials such as the galvanostatic charge–discharge performance and cyclic voltammetry were systematically measured. [Copyright &y& Elsevier]

The electrochemical performance of Fe2Al5 was investigated as an anode material for lithium-ion batteries. Fe2Al5 was prepared by arc melting the constituent elements, crushing to a suitable size and then ball milling. By removing samples from the ball mill at various times the effect of milling time on the electrochemical properties was examined. The highest discharge capacity (485 mAh/g) observed was as a result of ball milling for 10,000 min which is consistent with the theoretical capacity for formation of AlLi (543 mAh/g). Cyclic voltammetry and differential capacity plots, however, do not offer conclusive evidence of the formation of AlLi. Both charge and discharge capacity improved with increasing milling but cycle life remained poor. Removal of lithium from the structure was difficult with charge capacities being quite low. The first charge capacities for instance were in the range of 20–40% of the first discharge capacity. [Copyright &y& Elsevier]

Tin, tin oxide and NiSn-based nanocomposites with Al2O3 dispersion were prepared by ball milling to see their electrochemical properties as a new anode material for lithium-ion batteries. Electrochemical tests demonstrated that the initial charge–discharge capacities are very high for these materials. However, the capacity faded rapidly after the first cycle due to irreversible reactions. This is thought to be caused by the separation of the active materials from the inert oxide particles. The initial cycling efficiency was markedly improved by subsequent annealing of the ball-milled electrode. [Copyright &y& Elsevier]

Multiwall carbon nanotubes (MWNTs) were synthesized using chemical evaporation deposition (CVD). The morphology and microstructure of MWNTs were observed via HRTEM. The multiwall carbon nanotubes are entangled to bundles with a diameter of several tens of nanometers. Electrochemical properties of MWNTs were examined via a variety of electrochemical testing techniques. The MWNTs electrode demonstrated a reversible lithium storage capacity of 340 mAh/g with good cyclability at moderate current density. The kinetic properties of lithium insertion in MWNTs electrodes were characterized via ac impedance measurements. It was found that the lithium diffusion coefficient DLi decreases with an increase of Li-ion concentration in MWNTs electrodes. [Copyright &y& Elsevier]

The electrochemical performance of negative electrodes (anodes) made from mesocarbon microbeads (MCMB) in lithium-ion cells has been studied systematically via a variety of electrochemical techniques. The MCMB anodes have a stable lithium intercalation capacity of 325 mAh g−1 on high-rate charge–discharge cycling. Cyclic voltammetry shows only one reduction peak and one oxidation peak, which correspond to lithium-ion intercalation and de-intercalation, respectively. The diffusion of lithium ions in MCMB electrodes is characterized by ac impedance measurements. [Copyright &y& Elsevier]

Orthorhombic LiMnO2 with small grain size was successfully synthesised using a one-step middle-temperature solid-state reaction (OSSS). Compared with the methods other researchers used, the OSSS method is much simpler. It is a one-step method without intermediate regrinding or other treatments. The o-LiMnO2 obtained showed a high initial capacity 180 mAh/g when cycled at a current density of 0.5 mA/cm2 at room temperature, and the rate capability was improved due to the smaller particle size. Therefore, the one-step middle temperature solid-state reaction could be a promising method for o-LiMnO2 compound synthesis. [Copyright &y& Elsevier]

Cobalt oxides are investigated as anode materials for lithium-ion (Li-ion) batteries by means of a variety of electrochemical characterization techniques. The CoO electrode demonstrates a stable reversible lithium storage capacity of about 300 mAh g−1, even after 30 cycles. The reactivity of the cobalt oxides is attributed to the fact that the products of lithiation are in the form of nanosized products. [Copyright &y& Elsevier]

m-LiCrxMn1−xO2 solid solution has been synthesized by a solid state reaction method. The samples obtained show a first charging voltage of ∼4 V against a lithium electrode, but develops 4- and 3-V plateaus upon cycling, indicating transformation to spinel-like cation ordering within the oxide. Unlike previously reported lithium manganese spinels, the compound of this study shows excellent reversible capacity (>160 mA h/g at C/5 rate) when cycled over both the 4- and 3-V plateaus. The discharge capacity fade rate of samples decreases with an increase in Cr substitution, and H2SO4 treatment could further improve the electrochemical performance of samples. [Copyright &y& Elsevier]

This paper presents the microstructure and hardness of composite solders obtained by the addition of nanopowders of copper to a conventional solder. Copper powders-reinforced lead (Pb)–tin (Sn) composite solders were prepared by thoroughly blending nano-sized copper powders (average powder particle size 100 nm) with a powder of a eutectic solder and using a water-soluble flux. The blended solder paste was melted and allowed to re-solidify in a crucible placed on a hot plate and maintained at a constant temperature. Optical microscopy observations revealed the as-solidified microstructure of the composite solder to be altered by the addition of nanopowders to the eutectic Sn–Pb solder. The copper powders precipitated as intermetallic compounds that were non-uniformly distributed through the microstructure. Microhardness measurements revealed a 30–40% increase in hardness of the composite solder over the conventional unreinforced eutectic counterpart. [Copyright &y& Elsevier]

Investigates the resistance of Lindernia micrantha to sulfonylurea herbicides in Japan. Identification of biotype response to herbicide dose; Absence of resistance on the fields using herbicide rotations; Development of resistance after of soil carried from one original site to other site.

Abstract: We present a quantitative analysis on the effect of the spin–orbit interaction in the optical absorption of -electrons in graphene. It has been shown that the optical absorption amplitude of graphene around the K point in the Brillouin zone has a node in the two-dimensional Brillouin zone of honeycomb lattice. We calculated the k-dependent absorption matrix by taking into account the finite spin–orbit interaction in graphene. It was found that the spin–orbit interaction lifts the nodes in the absorption matrix. Furthermore, in the terahertz frequency regime, the spin–orbit interaction can significantly enhance the optical absorption in graphene, by up to 100%. [Copyright &y& Elsevier]

The aluminum alloy connecting rod of an air compressor was manufactured with liquid die forging replacing die casting and hot die forging. Not only were the defects of gas holes, porosity and non-metal inclusions in the die casting eliminated, but also the investment of the forging equipment and the performing process were decreased, and the coefficient of material utilization and the rate of production were increased. In this paper, the forging design, the die structure, the design parameters, and the technological advantages of liquid die forging for the aluminum alloy connecting rod are introduced. [Copyright &y& Elsevier]